Our studies in 1981 are a) on alanine turnover in vivo. b) The regulation of phosphofructokinase and futile cycling in rat liver cells and c) Gluconeogenesis and lipogenesis in avian (quail) hepatocytes. A. Alanine turnover and its contribution to gluconeogenesis in starved rats. 3-3H and U-14C alanine will be injected or infused. From the tracer kinetics the replacement rate of alanine and alanine mass, recycling of alanine carbon, and its role in glucose synthesis will be obtained. B. Hepatocytes from streptozotacin diabetic and diabetic insulin treated rats will be prepared. The randomization of 14C from 1-14C galactose in glucose will be determined. From this the rate of phosphofructokinase, and the effect of insulin treatment on cycling between Fructose-6P and Fructose 1,6 diP will be estimated. C. Gluconeogenesis and lipogenesis by hepatocytes from Japanese Quail (Coutournix coutournix). We have developed a preparation of liver cells from these birds. The rates of glucose synthesis and fat synthesis is several times higher than that in isolated rat liver cells. We have observed a large stimulation of glycolysis and lipogenesis from glucose in the presence of alanine. The effect of alanine on key glycolytic and lipogenic enzymes will be studied. The role of malic enzyme and isocitrate dehydrogenase in providing NADPH for fatty acid synthesis will be explored.